A filler spout is known, in particular from document FR-A-2 838 730, that comprises a tubular body having a main valve member mounted therein and associated with a valve seat for opening or closing the filler spout, the main valve member being connected to an electromagnetic actuator.
The electromagnetic actuator presents the advantage of controlling the main valve member without it being necessary to pass through the wall of the tubular body, such that that type of filler spout is particularly well adapted to packaging foodstuffs.
Nevertheless, because of the small amount of space available, it is not possible to provide magnetic parts that deliver a strong field. The force applied to the main valve member in order to open it is therefore limited and it is generally necessary to provide buffer vessels for the purpose of regulating pressure upstream from the filler spout. The presence of such buffer vessels constitutes a constraint in terms of the volume occupied by the buffer vessels close to the filler installation, and by the bacteriological problems that arise when a liquid foodstuff is stored in a buffer vessel.